There are many instances in our day to day activities where one needs to have a light switch tripped after one has left the immediate proximity of the switch. The delayed action switch actuator is a device which provides an answer to this need. A device of this type can be electrical or mechanical.
Electrical delayed action switch actuators, that is, devices which will electronically turn off the power after a time period, are generally more exact as to the reproducibility and the length of the time period than their mechanical counterparts. However, there are a number of difficulties inherent to this type of electrical device which are encountered by the manufacturer and consumer. First, an electrical device which is being added on to the existing electrical system of a house, no matter how simple, must comply with the operational parameters of the electrical system to which it is being added. This places restrictions on the type of components that can be used, both from a performance and a safety standpoint. Secondly, the installation of an electrical device requires tapping into the electrical system of the house, which entails turning the power off before commencing work and taking particular care to insure that all connections are made correctly to avoid shorts and other potential problems. It is not necessarily a trivial process. And finally, an electrical device that is being connected to a building's electrical system is generally subject to various levels of scrutiny and regulations by governmental organizations regarding its safety and performance so as to protect the consumer. This increases the overhead cost of each product, which ultimately results in a more expensive product to the consumer.
A mechanical delayed switch actuator avoids many of problems encountered by its electrical counterpart because it operates without direct intervention to the electrical system of the building. There are various patented devices which employ different mechanical means to throw a switch. The Bracken patent, U.S. Pat. No. 2,637,788, shows a spring-actuated time delay toggle switch actuator. It uses a pneumatic cylinder and a spring biased piston which extends to actuate the toggle. The Stevens patent, U.S. Pat. No. 3,499,132, shows a spring loaded striker pivotally mounted to the switch plate. The striker is released by suitable means, such as a falling weight actuated by some external event, such as the opening of a door.
The problem encountered in these devices is that they are relatively complicated in their design and operation for the simple task they perform. Aside from the absurdity of what would seem to be an overkill solution to a simple problem, the added complexity results in greater costs in material and production, which ultimately translates to a larger price tag for the consumer. Also, by making the device overly complicated, there are created a greater number of places and possibilities for malfunction, which will influence the overall utility of the device to the consumer.
Ideally, one would hope for an invention which would automatically trip a light switch with minimal hardware, minimal effort in installation and at minimal cost, while at the same time offer reliability and safety to the user. The present invention does just that.